G4 meter max kwts that can be run off it?

[billski]

Got to do a gas safety certificate on a big house!
Property has 3 boilers, range cooker and inset gas fire. Total of 70kwts.
Aprox 45 mtrs of 28 mm copper pipe.
Gas volume is 0.0347 so I'm just below the limit for domestic, but does any one know what the max kwts I can run off the G4 meter? And if I've got that all wrong pls let me know! Cheers.

 

[EvilDrPorkChop]

64kw.

 

[billski]

So it's running too many kwts, but I'm sure I read somewhere there is some sort of allowance calculation as it's highly unlikely every appliance would ever be running at max rate. Trouble is I can't find that calculation anywhere now!

 

[EvilDrPorkChop]

At 6kws over it's not much, i've heard G4 meters can nearly do 7m3/h. The easiest way would be to turn all the appliances on and Gas Rate it and see if the meter is reading the correct amount.

Can't say i've heard of the 'allowance' calculation, however as you say it's unlikely all the appliances will be at full load all at once.

Is 70kws the gross inputs of all the appliances?

 

[billski]

I think it's more likely 82 kwts now. Couldn't find the mi's for the duel fuel range cooker so estimated that was about 15kwts, just found it on line and it's 24!

 

[EvilDrPorkChop]

Should be a U16 meter then. Bit of a funny one though isn't it, i've got a customer in a very similar situation but more over than that. However they quoted him about £10k to upgrade the meter and main which he ain't going to do!

 

[billski]

Wow! Is it not possible to just switch the meter over then? Does the supplier charge for that?

 

[EvilDrPorkChop]

No as the incoming gas main wasn't big enough to handle a U16 meter. If they install a U16 meter the main has to support it, so it was a question of upgrading the lot. If you're incoming is only 25mm over a bit of a distance it ain't going to handle it. If you can get away with upgrade the meter they'll sure charge you just for that too! Any excuse.

If had issues on G4 meters recently where they've redone the gas mains up the old steel ones and we're only getting 17/18mb at the meter and that's only over 5/6 meters from the road.

 

[ShaunCorbs]

5k to switch to a u16

why 3 boilers?

also there diversion eg all wont be run at once

 

[billski]

Yeah I've just found the diversity factor calculation in my book. 3 boilers as 1 for 2 unvented hot water cylinders, 1 for ufh and rads plus 1 for a swimming pool. Don't know who installed it!

 

[ShaunCorbs]

i would say its on the limit


how you doing the gas safety on the pool boiler as thats a sep ticket

 

[billski]

Works out at 7.31m3 per hour with the diversity factors.

 

[EvilDrPorkChop]

Is it possible to range rate any of the boilers down a bit?

 

[billski]

Is it possible to range rate any of the boilers down a bit?

That's an idea!
They're all Potterton Pro max. 2 system boilers and one combi. I'll look it to it unless any one knows off the top of their head if they can be range rated?

 

[ShaunCorbs]

dont think so

 

[firemant]

Surely, done properly, the rating has to be done at MAXIMUM appliance consumption, and allow the diversity factor. From a practical point of view it would work, but does not make it comply. Not that it would necessarily be an issue, unless you are signing something off.

 

[billski]

Surely, done properly, the rating has to be done at MAXIMUM appliance consumption, and allow the diversity factor. From a practical point of view it would work, but does not make it comply. Not that it would necessarily be an issue, unless you are signing something off.

They're about to rent the property so needs a gas safety cert.

 

[EvilDrPorkChop]

Surely, done properly, the rating has to be done at MAXIMUM appliance consumption, and allow the diversity factor. From a practical point of view it would work, but does not make it comply. Not that it would necessarily be an issue, unless you are signing something off.

Surely that would depend on the appliance, if it’s an older appliance that could be range rated anywhere from 11 to 18kw you would go off the figure it is set as for it’s intended purpose.

 

[ShaunCorbs]

Surely, done properly, the rating has to be done at MAXIMUM appliance consumption, and allow the diversity factor. From a practical point of view it would work, but does not make it comply. Not that it would necessarily be an issue, unless you are signing something off.

Try telling that to the networks / meter people anywhere upto 7m3 on a 6m3 meter they will say it’s fine with diversity

 

[Harvest Fields]

Got to do a gas safety certificate on a big house!
Property has 3 boilers, range cooker and inset gas fire. Total of 70kwts.
Aprox 45 mtrs of 28 mm copper pipe.
Gas volume is 0.0347 so I'm just below the limit for domestic, but does any one know what the max kwts I can run off the G4 meter? And if I've got that all wrong pls let me know! Cheers.

How is 70kw below the limit?